The present invention is broadly directed to surgical instruments, and more specifically to instruments useful in arthroscopic surgery and similar surgical procedures wherein access to the surgical site is limited and/or difficult.
The surgical environment of the invention normally involves performance of surgical procedures through small incisions through which the instruments are introduced and subsequently manipulated. With the use of surgical cutting instruments, for example cutting blades, substantial care must be taken not only in the cutting manipulation thereof, but also in the actual introduction of the cutting blade to the cutting site and the subsequent removal therefrom.
A problem associated with the cutting manipulation of surgical cutting instruments is the difficulty in stabilizing the tissue as the tissue is cut. This is particularly the case wherein use of a single instrument is desired or required for minimal body invasion and/or trauma.
As noted in substantial detail in Aikens, U.S. Pat. No. 4,491,132, issued Jan. 1, 1985, one known procedure for the atraumatic introduction of a cutting instrument utilizes a protective sheath. The sheath, a linear hollow member, has the blade completely received and sheathed therein. The blade remains in the sheath until the distal or forward end of the sheath is positioned proximate the site of use. At that time, the blade is mechanically extended from the sheath, either by an actual extension of the blade from the sheath or by a corresponding retraction of the sheath relative to the blade. The Aikens patent notes the desirability for such instruments and discloses selected variations thereof.
The necessity for surgical procedures in limited access environments has also led to the development of instruments incorporating means for guiding a cutting blade or the like during the actual use thereof at the cutting site. Such known means include opposed guides or tracks along which the blade travels during the cutting operation. In this regard, note the following:
______________________________________ Roberts et al U.S. Pat. No. 3,835,859 Sept. 1, 1974 Le Noir U.S. Pat. No. 4,067,340 Jan. 10, 1978 ______________________________________
The instruments of both Roberts et al and Le Noir are rather cumbersome, requiring the use of separate handles to adjust and position the guide and subsequently manipulate the blade.
Copending application Ser. No. 780,895, Allen H. DeSatnick, filed Sept. 27, 1985, now patent number commonly owned with the present application, discloses a sheath and blade assembly. The sheath functions both as a bladeenclosing protective means and as a blade guide during surgical cutting. The sheath and blade assembly are removably mountable on a reusable handle incorporating an actuation mechanism for manipulation of the blade relative to the sheath utilizing a single slide button. The disclosure of the DeSatnick application, Ser. No. 780,895, is herein incorporated by reference.